1. Field of the Invention
The invention concerns an engine arrangement having a gas engine, in the exhaust gas tract of which there is preferably arranged an exhaust gas catalytic converter. Arranged in the propellent gas feed line to the gas engine is at least one cleaning device for the adsorptive cleaning of the propellent gas, which includes a regeneration device for regeneration of the adsorption agent.
2. Description of the Related Art
When using internal combustion engines (gas engines) for using the energy of biogases (in particular sewer gases or disposal site gases), the use of an exhaust gas catalytic converter has hitherto not been economically meaningful because trace substances contained in the propellent gas have a strongly adverse effect on the activity of the exhaust gas catalytic converter in a short period of time.
It is already known that the propellent gas can be freed of catalyst poisons by means of an adsorptive cleaning device (U.S. Pat. No. 4,523,548 A).
The capacity of the adsorption agent (in particular activated carbon) is limited. It was therefore hitherto frequently necessary to replace the adsorption agent at or shortly before attainment of a condition of saturation. Since the replacement of the adsorption agent by a fresh adsorption agent and disposal of the charged adsorption agent represents a considerable cost factor, it has already been proposed that the adsorption agent should be regenerated, in particular by being heated (U.S. Pat. No. 4,523,548 A). In that regeneration operation the adsorption agent can remain in the cleaning device. It is only freed of the trace substances (biogas accompanying substances or impurities) adsorbed from the propellent gas. In U.S. Pat. No. 4,523,548 A however the trace substances which are driven out of the adsorption agent are fed to the engine again, which in accordance with the object of the present invention is precisely to be prevented.